Abstract: Portable radiotelephone including a central processing unit, a transmit and receive radio circuit connected to at least one antenna, a microphone emerging upwards when the radiotelephone is worn by means of a necklace, a speaker and a keypad that includes at least one multifunction key.

Abstract: The invention relates to a local radio communication system comprising a central controller (9), several bases (7) which are connected to the controller and several terminals (5) which communicate with the bases. The bases (7) communicate with the terminals using a local radio communication protocol with time division multiple access. Said bases are adapted to real-time transmit chronological information to the controller releasing to the transmissions planned for said bases. The controller is adapted to determine if there is a risk of interferences occurring between the planned transmissions and to impose a chronology for said planned transmissions on the bases in order to limit said interferences.

Abstract: The invention concerns a central base for a private wireless local area network wherein the central base includes electronic circuits that include an electronic central unit and which is supplied with electricity with at least one live supply line intended to be connected to an external electricity power source. The central base is suitable for communicating on the one hand with a public telecommunication network, and on the other hand with at least one wireless peripheral device according to a digital bi-directional wireless protocol for a private wireless local area network.